Autoimmune Clinical Features and Thyroid Antibody Profiles in Black South Africans with Toxic Graves and Primary Hypothyroidsim

Abstract

Background: There are few published reports on the clinical characteristics of auto-immune thyroid disease in the African. Objectives: To assess the clinical features Thyrotropin Receptor (TR) and Thyroid Peroxidase (TPO) antibodies in Toxic Graves’ and Spontaneous Primary Hypothyroidism (SPH). Methods: Cross sectional study of black African patients with Toxic Graves’ and SPH attending an Endocrine Clinic in the Eastern Cape province of South Africa over the 5 year-period from March 1, 2008 to February 28, 2013. Data on age, gender, type and duration of thyroid disease, thyroid antibodies were collected. The clinical features and percentages of patients with Toxic Graves’ and SPH who were positive for TR and TPO antibodies were assessed. Results: There were 42 patients with Toxic Graves and 15 with SPH. Both patients’ groups were dominantly female with ages of 37.5 ± 12 and 46 ± 21.6 years; P=0.06 respectively. The TR and TPO antibodies positivity rates in Toxic Graves’ were 80.5% and 65% respectively. The TR and TPO antibodies rates in SPH were 8.3% and 40% respectively. Conclusion: Toxic Graves’ in our black African patients is associated with high rate of TR antibody positivity. The low rate of TPO antibodies in our SPH patients may suggest non-immune etiology in the majority of patients with SPH.